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Musty Smell with New Central Air Unit

Hi everyone.

After 2.5 weeks of excruciating heat waves and a broken down central air unit, my building management finally installed a new unit in my apartment. It's a 2 ton unit, same as the old one, but brand new. It was a 12 hour job, due to how old the building is, etc. But ever since the replacement, every time the cool air comes on on auto, the air carries out a musty smell which was never there before. It's so bothersome to me that I've been sneezing all day, have a runny nose, watery/burning eyes, and now my throat hurts. Management called in the guy who replaced the unit and he said he didn't smell anything - which was not surprising, given he smelled of cigarette smoke! He said he was going to talk with his boss and maybe he will come in and check. Today, they are putting this smell issueback on the manager instead of coming out to check into it as the guy from last night promised. They are saying management may need to clean the ducts. However, that won't happen until Monday, and I'm in a state of constant allergic reaction since the replacement. And, I don't think that the clean duct is the issue.

I'm on the top floor of the building, no attic, unit is on the roof, and duct work is in a dropped ceiling in the unit hallway and there are 4 vents. What could this smell be coming from?!

Also, the air flow from the vents is a lot less than when the old system was in place. The filter is new, the unit is new, they replaced a whole bunch of stuff (potentially even a new heat pump, I think), and yet air flow is lower than the old one, and the smell is bad.

Please realize I rent, so I don't have access to the unit on the roof, nor further info than I've provided than above, due to management. But can you give me some input/suggestion?

Just to reiterate, the smell is at its worst when the air kicks on (on auto), and its every, single time. It hasn't gotten better or less in two days...it's constant, esp. strongest when the cool air turns on. By the way, it doesn't smell like dirty socks..it smells like a damp rag that hasn't been aired out - not dirty smell, but like a damp attic smell.

I live in Los Angeles, so humidity varies between 20-40% in the summer, much less in winter.

The smell actually is getting worse. My manager commented that the installers used some kind of "grease" before putting the insulation on near the ducts and she said that smelled pretty bad. I don't know what she's talking about (do you all?), but the smell is pretty bad...simething like a combination of glue, water, metal, musty...something that lingers in the home and burns my eyes/throat. Everything is electric, not gas..because I would almost say it smells somewhat like gas, too.

Ok, I think I figured out what the smell is...but now I need this community's help to direct me to the next best step.

I spoke with management about the smell and she said when they were installing the a/c, the techs put some kind of "grease" on the pipes near the air return vent so they could get the pipes in easier. She admitted the smell of the "grease" made her feel ill at the time, too.

Well, I finally noticed that the smell is strongest right near where the pipes/ducts are insulated near the air return. It's a very strong burning chemical smell and as soon as the air comes on, the smell kicks out of the vents.

Can someone please tell me what this "grease" is called and how do I get the install techs to remove it?? I had an asthma attack last night because of the smell - I haven't had one in 15 years!

Can you sleep elsewhere for the next few days? Whatever it is (and I have no idea), if I were you I wouldn't sleep there until it's gone, or I'd turn off the system, open the windows and try to be comfortable with fans.

how to find out what "grease" substance they used

Originally Posted by Holli

Ok, I think I figured out what the smell is...but now I need this community's help to direct me to the next best step.

I spoke with management about the smell and she said when they were installing the a/c, the techs put some kind of "grease" on the pipes near the air return vent so they could get the pipes in easier. She admitted the smell of the "grease" made her feel ill at the time, too.

Well, I finally noticed that the smell is strongest right near where the pipes/ducts are insulated near the air return. It's a very strong burning chemical smell and as soon as the air comes on, the smell kicks out of the vents.

Can someone please tell me what this "grease" is called and how do I get the install techs to remove it?? I had an asthma attack last night because of the smell - I haven't had one in 15 years!

The simplest thing is to request or demand in writing that your manager find out from the installer what substance the installer applied to the ducts to "grease" them. They have the answer, so why not try there first? This must be an issue that they will want to avoid in the future, too.